Improvement in lightning-rods



2 sheetswsheet 1. J. HEWITT. Lightning-Rods.

NO. 211,847. Patented Feb. 4,1879.

2 Sheets-Sheet 2.

J. HEWITT. Lightning-Rods.

No. 211,847. Patented Feb. 4,1879.

N- PETERS. PHDTDJJTHOGRAPNER. WASHINGTON. D. G.

EJITHD STATES PATENT FFIC .IoHN HnwITT, or cHIcAeo, ILLINOIS.

IMPROVEMENT IN LIGHTNING-RODS.

Specification forming part of Letters Patent No. 211,847., datedFebruary 4, 1879 application tiled October 29, 1878.

To all whom it may concmn:

Beit known that I, JOHN HEwITT, of Ghicago, in the county of Cook andState of Illinois, have invented certain new and useful Improvements inJoints for Lightning-Rods; and I do hereby declare that the following isa full, clear, and exact description of the invention, which will enableothers skilled in the art to which it pertains to make and use the same,reference bein ghad to the accompanying drawings, and to the letters ofreference marked thereon, which form a part of this specification.

My invention relates to an improvement in joints for lightning-rods 5and consists in securing the sections together by means of a tube, theinner wall of which is provided with screwthreads, and screw-threads ator near the ends of the sections, the whole constructed and arranged forthe purpose of bringing the ends of thesections in contact with eachother, thereby forming a continuous conducting medium of the same metalor combination of metals constituting the body of the lightning-rod.

To enable others skilled in the art with which my invention is mostnearly connected to make and use it, I will proceed to describe itsconstruction and operation.

In the accompanying drawings, Figure lis a side view of my improvementin joints for lightning-rods, representing it when used on the rod inthe untwisted form. Fig. 2 is a longitudinal section of the same. Fig. 3is a transverse section of the same. Fig. 4 is a transverse section ofthe joint, representing the screw-threads ou the rod as only partlyencircling the rod. Fig. 5 is a longitudinal section of the same. Fig. 6is a side view of my improvement in joints, representing the same whenapplied to the twisted form of lightning-rod, the body of which isformed of oval iron surrounded with sheet-copper. Fig. 7 is a transversesection of the same. Fig. 8 is a side view of my improvement in jointswhen applied to the twisted form of lightningrod, the body of which isconstructed of iron known as star iron, surrounded with sheetcopper, thescrew-threads being attached to the sections by sockets, the screw-threads being on the socket. Fig. 9 is a cross-section of Fig. 8.

, In the accompanying drawings, A represents the tube, havingscrew-threads on its inner wall. This tube may be constructed ot' iron,brass, copper, or other suitable metal. B represents the screw-threadson the rod D, which screw-threads are formed 011 a cylinder, the bore ofwhich conforms to the contour of the rod D when viewed in cross-section,and is secured to the rod by the process of brazing, riveting, or anyother desirable means that may suggest itself to the mind of themechanic. The cylinder having screw-threads B may, on one end of eachsection of the rod D, have a ange or shoulder, to serve the purpose of astop for the tube A, as indicated at G in Fig. l. The screw-threads Bmay be secured on the rod D in sections, as shown in Figs. 4 and 5, orthey may be formed on a socket, which is shown at E in Fig.' 8, whichsocket is bent into the grooves in the rod D, as shown in Fig. S at f,and secured to the rod D by rivets, as shown at g.

In the operation of uniting two or more sections of the lightning-rod Btogether, the tube A is moved back on the rod, as indicated by thedotted lines iu Fig. 6, and the two ends of the sections of the rod Dare brought close together and united thus by screwing the tube A overthe screws B, as shown in Fig. 2, thereby bringing the ends of twosections close together, causing them to press hard against each other,and forming a close union, in which position they are permanently heldby the tube A. By this arrangement of joint one continuous line ofconductor is formed of the metal constituting the body of the rod, whichis the thing desired in a lightning-rod.

The screw-threads on the rod D may be formed in two sections, as shownat B in Figs. 4 and 5, and secured in the angles of the rod D by rivetsor the brazing process.

The peculiarity of construction of my improvement in joints forlightning-rods, besides securing an unbroken and continuous line ofconductor of the metal or combination of metals which form the body ofrod, also greatly diminishes the labor and expense of placing the rod inposition on the building to which it may be applied. All the necessarycurves in the rod may be made in order to adapt it to the contour of thewalls, cornice, and roof of the building, and the union of the severalsections of the rod subsequently effected with as much ease as could bedone if the rod were perfectly straight. The advantages of being enabledto form the union between the several sections of the rod after beingbent to the contour of the walls, cornice, and roof of the building willbe very apparent to all who have any experience in placinglightning-rods, the curves and bends of the rod a1- ways impedin g theformation of the union between the sections of the rod, and very oftenresulting in serions accident to the operator.

I am aware that unions have been formed between two sections of pipe,also between two sections of shafting and other things, by the use of ashort tube having screw-threads on its inner wall, combined withscrew-threads on `such pipe, shafting, and other thing; therefore I donot claim, broadly, a tube having screw-threads on its inner wall whencombined with screw-threads on pipes, shafting, and other things as nowused in the arts among mechanics; but I am not aware that such devicewas ever used for` forming a close union between the ends of pipes,shafting, and other things, as in the case of the lightning-rodhereiubefore described.

What I claim is- 1. The method herein described of forming a close unionbetween the ends of the sections of the rod D by means of the tube A andscrews B ou the rod D, the diameter of the bore of said tube A beinggreater than the largest diameter of the rod D, as and for the purposeset forth.

2. In a joint for lightning-rods, the tube A, in combination with thesections B B, provided with screw-threads B' B', secured in the anglesof the rod D, substantially as herein described.

In testimony that I claim the foregoing as my own invention I affix mysignature in presence of two witnesses.

JOHN HEWITT.

Witnesses:

Jos. T. K. PLANT, J. A. PATTERSON.

